The object of the proposed research is to continue to evaluate articular cartilage viability, metabolism, and physical properties following various methods of storing cartilage and following joint resurfacing with preserved, viable cartilage. Both rabbit and human in vitro articular cartilage models are to be characterized as to 1) mucopolysaccharide, collagen, and protein synthesis and degradation; 2) cellular replication and histologic and histochemical properties; and 3) physical properties including viscoelastic response; shear, compressive, and tensile strength; maximum repetitive cyclic loading limit; and permeability and solute distribution coefficients. Methods to be utilized include scintillation counting of uptake and release of 35SO4, C14-L-proline and glycine-H3; amino acid analysis for proline, hydroxyproline, and glycine; autoradiography, microradiography, and selected histochemical stains; mechanical testing utilizing the CGS/Lawrence Dynamic Tensile Testing Machine and the Instron Tensile Testing Machine; and diffusion chamber techniques. Whole cartilage fragments are to be stored at 37 degrees C utilizing tissue culture techniques for varying periods of time. Following preservation, the methods used in characterizing the in vitro models are again employed to determine cartilage survival and fitness. Similarly, denuded rabbit medial femoral condyles are to be resurfaced with preserved articular cartilage, and viability, metabolism, and physical properties following transplantation are to be evaluated by the methods above.